Answer:
KEEP CEILING WHITE if you prefer
paint most walls a black or dark grey theme and have one white, red, hot/diva pink, or a light grey or most white with one that extra color you want
put down a light/dark grey wood/carpet floor
get black furniture or paint furniture black
find black picture frames and put edgy, sad, angry, or dark eligant and beautiful pictures in them
get black or red bedsheets, pillowcases, and curtains
with vases for flower décor you may want something bright that will pop out as long as it matches décor (color examples: red, white, hot/diva pink)
get fake red roses flowers (looking dead or alive) or get dried red roses.
glass jar full of dried roses
jar half filled with fake blood
edgy posters
sad/edgy quoted in few picture frames preferably one or two on desk and few an walls
get small fuzzy black or white décor carpet
have a few fictional vampire werewolf romance novels and keep on shelf for esthetic
I hope this helps you or anyone and I plan to do this with my room one day.